Orbital leiomyosarcoma metastasis presenting prior to diagnosis of the primary tumor

Abstract

Leiomyosarcomas, neoplasms of smooth muscle, are rarely found within the orbit. Orbital leiomyosarcoma may be primary, metastatic, or secondary to radiation. When they are metastatic, patients almost exclusively have a history of a primary leiomyosarcoma, often occurring in the spermatic cord, skin, gastrointestinal tract, or the uterus. We present the case of 48-year-old woman who presented with a metastatic orbital leiomyosarcoma, which was identified before the primary tumor.

FIG 1.

A, Patient’s initial visual field, with a full visual field in the right eye and a superior arcuate defect in the left eye resulting from her underlying glaucoma. B, Worsening of the visual field in the left eye, with a more significant superior visual field defect extending to the inferotemporal region.

FIG 2.

The figure demonstrates axial magnetic resonance imaging T1-weighted pre- (A) and post-contrast (B) images showing a well circumscribed lesion in the left orbital apex that diffusely enhances but with prominent rim enhancement; the lesion is inseparable from the left lateral rectus muscle.

FIG 3.

Computed tomography (A) and 18-fluorodeoxyglucose positron emission tomography (18-FDG PET; B) showing findings of the uterine leiomyosarcoma. There is an 8.5 cm heterogeneously enhancing lesion in the right lower quadrant with hypermetabolic activity as noted by the avidity of 18-FDG to the tumor.

FIG 4.

On hematoxylin and eosin stained sections, the pathology of the uterine tumor demonstrated spindle-shaped cells with eosinophilic cytoplasm and elongated, cigar-shaped nuclei with mitotic figures and areas of ischemic degeneration (A). The lesion was immunopositive for desmin (B) and smooth muscle actin (C), in keeping with a leiomyosarcoma. Original magnification ×400.

FIG 5.

T1-weighted pre- (A) and postcontrast (B) magnetic resonance imaging (MRI) demonstrating interval enlargement of the orbital lesion with compression of the left optic nerve.

FIG 6.

A, Orbital apex periorbita (*) exposed in a cranio-orbitozygomatic approach; the frontal lobe dura (F) and temporal dura (T) are noted beneath cottonoids. B, Periorbita is open and the lateral rectus (LR) reflected, showing the tumor (arrow). C, After resection of the tumor. D, T1-weighted post-gadolinium MRI 2 months after surgery showing no evidence of residual or recurrent tumor.